$(function(){
  $('div.row:has(span.required)').find('input, select').blur(function(){
    e = $(this);
    
    // First test for select, cause expr :input also includes select tags
    if( e.is('select') ){
      (e.attr('value') == 0)? e.siblings('.error').show(): e.siblings('.error').hide();
    }
    else if( e.is(':input') ){
      (jQuery.trim(e.attr('value')) == '')? e.siblings('.error').show(): e.siblings('.error').hide();
    }
  });
});